Inter and intraobserver variability in the echocardiographic measurement of vegetations in infective endocarditis

Introduction and objectives

The indication for surgery to prevent embolism in infective endocarditis includes four clinical scenarios and three different echocardiographic measurements of the maximal vegetation diameter. These cut-off points are completely arbitrary and not evidence-based. Our hypothesis is that the vegetation diameter is not an appropriate surgical criterium. The goal of the study is to analyze the inter and intra-observer variability in this measurement and to compare the surgical indications agreement based on these parameters.

Methods

Two trained echocardiographers have measured the maximal vegetation diameter by transesophageal echocardiogram in 67 consecutive patients with definite infective endocarditis in an off-line workstation. The inter- and intra-observer variability was calculated by the interclass correlation coefficient and with the Bland-Altman analysis. The relationship between the strength of agreement for the cut-off points of 10 and 15 mm was also calculated.

Results

Intra and inter-observer interclass correlation coefficient in the measurement of the maximal longitudinal diameter of the vegetations were 0.872 (0.805–0.917) and 0.757 (0.642–0.839) respectively. The strength of agreement of the intra and inter-observer analysis for the cut-off point of 10 mm were 0.674 (0.485–0.862) and 0.533 (0.327–0.759). For the cut-off point of 15 mm they were 0.696 (0.530–0.862) and 0.475 (0.270–0.679).

Conclusions

The variability in the measurements of the maximal longitudinal diameter by transesophageal echocardiogram between two experimented echocardiographers is good. Nonetheless, surgical indications based on the cut-off points recommended in the European guidelines would have changed in an unacceptable high proportion of patients. Therefore, we suggest that these indications should be revised in the light of our results.

Funding Acknowledgement

Type of funding source: None

Prognostic benefit of urgent cardiac surgery in left-sided infective endocarditis

Background

Cardiac surgery is required in approximately 50% of patients with left-sided infective endocarditis (IE) being a high-risk procedure specially during active phase of the disease.

Purpose

To evaluate the impact of cardiac surgery in the in-hospital mortality of left-sided IE.

Methods

We used a prospective cohort of consecutive patients with definite left-sided IE between 2000 and 2017 (n=1002). A predictive model of in-hospital mortality was derived by adding the variable cardiac surgery to the already published ENDOVAL score. The benefit of cardiac surgery was calculated with the mean difference between the risk of in-hospital mortality considering urgent surgery and considering no surgery for each patient.

Results

The predictive model showed good discriminative capacity with an area under the ROC curve of 0.861 (95% CI: 0.830 - 0.891) and a good calibration (p-value in the Hosmer-Lemeshow test of 0.353). Figure shows the in-hospital mortality prediction of each patient in case of no-surgery (orange), urgent surgery (yellow) or real decision (blue). Mean reduction of in-hospital mortality risk in case of surgery for patients with a theoretical risk of in-hospital mortality between 0–20% in absence of surgery was 3.2±1.6%. For patients with a theoretical risk between 20–40% in absence of surgery the mean reduction was 8.1±1.1%. For patients with a theoretical risk between 40–60% in absence of surgery the mean reduction was 10.7±0.3%. For patients with a theoretical risk between 60–80% in absence of surgery the mean reduction was 9.7±0.9%. For patients with a theoretical risk between 80–100% in absence of surgery the mean reduction was 4.6±2.1%.

Conclusion

Urgent cardiac surgery is a protective factor of in-hospital mortality for all patients with left-sided IE but especially for those with intermediate risk.

Figure 1

Funding Acknowledgement

Type of funding source: Public Institution(s). Main funding source(s): Gerencia Regional de Salud, Junta de Castilla y Leόn

The 3 noes right-sided infective endocarditis: a unrecognized type of right-sided endocarditis

Introduction

The “3 noes right-sided infective endocarditis” (3no-RSIE: no left-sided, no drug users, no cardiac devices) was depicted for the first time more than a decade ago. We describe the largest series to date to characterize its clinical, microbiological, echocardiographic and prognostic profile.

Methods

Eight tertiary centers with surgical facilities participated in this study. Patients with right-sided endocarditis without left involvement, absence of antecedents of drug use and no intracardiac electronic devices were retrospectively included in a multipurpose database. A total of 53 variables were analysed in every patient. We performed a univariate analysis of in-hospital mortality to determine variables associated with worse prognosis.

Results

A total of 100 patients (mean age 54.1±20 years, 65% male) with definite 3no-RSIE were included (16.7% of all the right-sided endocarditis of the series). Most of the episodes were community-acquired (72%), congenital cardiopathies were frequent, fever was the main manifestation at admission (85%). The microbiological profile is led by Staphylococci spp. Vegetations were detected in 92% of the patients. Global in-hospital mortality was 19% (5.7% in patients operated and 26% in patients who received only medical treatment, p<0.001). Non community-acquired infection, diabetes mellitus, right heart failure, septic shock and acute renal failure were more common in patients who died.

Conclusions

The clinical profile of 3no-RSIE is closer to other types of RSIE than to LSIE, but mortality is higher than that reported on for other types of RSIE. Surgery plays an important role in improving outcome.

Funding Acknowledgement

Type of funding source: None